TECH TALK
emerging as both the most sustainable and the only viable path forward. Without it, keeping pace with increasing power densities and heat demands simply won’ t be possible.
Not only can liquid cooling cut energy use by 30-60 %, it can also eliminate water consumption altogether, providing efficiency gains that adiabatic cooling can’ t match. In turn, savings in energy and water directly translate into carbon footprint savings. Yet even as adoption of liquid cooling rises, its full sustainability impact remains less understood compared to air.
Liquid cooling’ s broader adoption will require a deeper look into several data centre design and operational levers. These levers can impact key sustainability categories:
• Energy use: Next to IT systems, the cooling system is the secondbiggest energy consumer for data centres. Potential energy savings can be significant, making this a primary sustainability consideration for liquid cooling deployments. Energy use is driven by a range of design and operational decisions, from foundational site selection and climate considerations to detailed factors like heat rejection systems and IT inlet fluid temperature set points. By evaluating these decisions, operators can accurately understand how their cooling systems affect sustainability.
• Water use: Data centre water consumption can vary widely depending on factors such as heat rejection system design( evaporative or adiabatic cooling), local climate and IT inlet fluid temperatures. The liquid cooling loop is a closed system; therefore, racks do not consume water directly. However, the data centre’ s overall water footprint is still influenced by how heat is ultimately rejected outdoors. Operating at higher temperatures, liquid cooling can reduce reliance on outdoor water for heat rejection. Like energy use, water consumption remains a direct and measurable environmental impact that operators can manage and optimise.
• Greenhouse Gas( GHG) emissions: While carbon footprint is influenced by decisions made throughout the cooling system’ s life cycle, such as component selection and water use, it is primarily driven by energy consumption, especially if the grid relies heavily on fossil fuels.
Another lever to keep in mind is coolant toxicity. While direct-to-chip liquid cooling is deployed as a closed-loop system, safe operations and responsible disposal are critical.
Designing for sustainability: Key decisions impacting AI data centres
Installing liquid cooling is a great first step in the age of AI, but it’ s not enough. True sustainability stems from smart
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